Antiferromagnetism in four dimensions: search for non-triviality

We present antiferromagnetism as a mechanism capable of modifying substantially the phase diagram and the critical behaviour of statistical mechanical models. This is particularly relevant in four dimensions, due to the connection between second order transition points and the continuum limit as a quantum field theory. We study three models with an antiferromagnetic interaction: the Ising and the O(4) Models with a second neighbour negative coupling, and the \RP{2} Model. Different conclusions are obtained depending on the model.Comment: 4 pages LateX. Contribution to Lat9

Pattern formation in a predator-prey system characterized by a spatial scale of interaction

We describe pattern formation in ecological systems using a version of the classical Lotka-Volterra model characterized by a spatial scale which controls the predator-prey interaction range. Analytical and simulational results show that patterns can emerge in some regions of the parameters space where the instability is driven by the range of the interaction. The individual-based implementation captures realistic ecological features. In fact, spatial structures emerge in an erratic oscillatory regime which can contemplate predators' extinction.Comment: 5 pages, 4 figure

Appearance of pyrophyllite as replacements of spiriferids (Brachiopoda) Shells of the devonian in the Central-Iberian zone (Hesperic Massif, Spain).

[Abstract] Amacroscopic pyrophyllite bearing mineralization related to shells ofspiriferids has beeen found in the Herrera Formation (southern Central-Iberian Zone, Hesperic Massif, Spain). The observed mineral asociation is pyrophyllite + nacrite + quartz + calcite + anhydrite, and it is interpreted as resulting from the substitution ofinitial carbonatic shell by a Si, Al, S rich hydrothermal solutio

Tratamiento quirúrgico de las roturas del tendón de Aquiles

El objetivo del trabajo fue valorar los resultados y complicaciones obtenidos tras tratamiento quirúrgico de las rupturas subcutáneas del tendón de Aquiles. Se revisaron 26 pacientes, con un seguimiento mínimo de 1 año. Detallamos nuestra metodología en cuanto a técnica quirúrgica y manejo postoperatorio. Se valoró el resultado clínico según los siguientes parámetros: movilidad de tobillo, potencia muscular tríceps, engrosamiento tendinoso, claudicación a la marcha, atrofia gemelar, incorporación a actividades deportivas y alteraciones residuales. Los resultados fueron muy buenos en 21 casos (80,7%); buenos en 5 (19,3%), y ningún caso con resultado regular o malo. Destacamos 5 complicaciones postoperatorias inmediatas y 1 caso de reruptura, con resultado final satisfactorio. Dados los buenos resultados obtenidos, recomendamos el tratamiento quirúrgico en pacientes activos, con buen estado general, independientemente de la edad.The objective of this work was to asess the clinical results and complications with the surgical treatment for subcutaneous Achilles tendon ruptures. Twenty six patients were clinically revised with a minimal follow up of one year. We detailed the surgical technique and postoperative management of the patients. Clinical results were assessed with the next parameters: ankle joint motion; triceps muscle strength; Achilles tendinous thickened; walking limp; triceps muscle atrophy, possibility of sports practice and definitive changes. We had excellent results in 21 cases (80,7%); good results in 5 cases (19,3%) and none with fair or poor results. We detached 5 cases with immediate postoperative complications and one case of relapse, all of them with good clinical result. Our excellent and good clinical results with the surgical technique for the Achilles tendon ruptures allow us to recommend this treatment in active patients, with appropriate health conditions in spite of the age

Caracterización de aceites de oliva virgen europeos usando ácidos grasos

The possibility of discriminating between extra virgin olive oils from different regions of Spain, Italy and Portugal, by means of their fatty acid content, has been investigated. A dendrogram allowed discrimination between the oils starting from their initial grouping and progressing to differentiation on the basis of regions. Multivariant statistical analyses were applied to determine the actual discriminatory capacity of this group of compounds. The confidence associated with the final discrimination was ascertained using the theory of evidence.Se ha estudiado la posibilidad de discriminación entre aceites de oliva virgen procedentes de diferentes regiones de España, Italia y Portugal, mediante sus ácidos grasos. Para llevar a cabo la discriminación entre los aceites, desde su agrupación inicial hasta la diferenciación por regiones, se empleó una estructura arborescente. Fueron aplicados procedimientos estadísticos multivariantes para determinar la capacidad discriminante actual de este grupo de compuestos. La certeza asociada a la discriminación final fue calculada mediante la teoría de la evidencia

Effects of preeclampsia and eclampsia on maternal metabolic and biochemical outcomes in later life: a systematic review and meta-analysis

Objective: To evaluate the association between preeclampsia (PE) and eclampsia (E) on subsequent metabolic and biochemical outcomes. Methods: Systematic review and meta-analysis of observational studies. We searched five engines until November 2018 for studies evaluating the effects of PE/E on metabolic and biochemical outcomes after delivery. PE was defined as presence of hypertension and proteinuria at >20 weeks of pregnancy; controls did not have PE/E. Primary outcomes were blood pressure (BP), body mass index (BMI), metabolic syndrome (MetS), blood lipids and glucose levels. Random effects models were used for meta-analyses, and effects reported as risk difference (RD) or mean difference (MD) and their 95% confidence interval (CI). Subgroup analyses by time of follow up, publication year, and confounder adjustment were performed. Results: We evaluated 41 cohorts including 3300 PE/E and 13,967 normotensive controls. Women were followed up from 3 months after delivery up to 32 years postpartum. In comparison to controls, PE/E significantly increased systolic BP (MD = 8.3 mmHg, 95%CI 6.8 to 9.7), diastolic BP (MD = 6.8 mmHg, 95%CI 5.6 to 8.0), BMI (MD = 2.0 kg/m2; 95%CI 1.6 to 2.4), waist (MD = 4.3 cm, 95%CI 3.1 to 5.5), waist-to-hip ratio (MD = 0.02, 95%CI 0.01 to 0.03), weight (MD = 5.1 kg, 95%CI 2.2 to 7.9), total cholesterol (MD = 4.6 mg/dL, CI 1.5 to 7.7), LDL (MD = 4.6 mg/dL; 95%CI 0.2 to 8.9), triglycerides (MD = 7.7 mg/dL, 95%CI 3.6 to 11.7), glucose (MD = 2.6 mg/dL, 95%CI 1.2 to 4.0), insulin (MD = 19.1 pmol/L, 95%CI 11.9 to 26.2), HOMA-IR index (MD = 0.7, 95%CI 0.2 to 1.2), C reactive protein (MD = 0.05 mg/dL, 95%CI 0.01 to 0.09), and the risks of hypertension (RD = 0.24, 95%CI 0.15 to 0.33) and MetS (RD = 0.11, 95%CI 0.08 to 0.15). Also, PE/E reduced HDL levels (MD = –2.15 mg/dL, 95%CI –3.46 to −0.85). Heterogeneity of effects was high for most outcomes. Risk of bias was moderate across studies. Subgroup analyses showed similar effects as main analyses. Conclusion: Women who had PE/E have worse metabolic and biochemical profile than those without PE/E in an intermediate to long term follow up period. ©Revisión por pare

Accumulated bending energy elicits neutral sphingomyelinase activity in human red blood cells

We propose that accumulated membrane bending energy elicits a neutral sphingomyelinase (SMase) activity in human erythrocytes. Membrane bending was achieved by osmotic or chemical processes, and SMase activity was assessed by quantitative thin-layer chromatography, high-performance liquid chromatography, and electrospray ionization-mass spectrometry. The activity induced by hypotonic stress in erythrocyte membranes had the pH dependence, ion dependence, and inhibitor sensitivity of mammalian neutral SMases. The activity caused a decrease in SM contents, with a minimum at 6 min after onset of the hypotonic conditions, and then the SM contents were recovered. We also elicited SMase activity by adding lysophosphatidylcholine externally or by generating it with phospholipase A 2. The same effect was observed upon addition of chlorpromazine or sodium deoxycholate at concentrations below the critical micellar concentration, and even under hypertonic conditions. A unifying factor of the various agents that elicit this SMase activity is the accumulated membrane bending energy. Both hypo-and hypertonic conditions impose an increased curvature, whereas the addition of surfactants or phospholipase A 2 activation increases the outer monolayer area, thus leading to an increased bending energy. The fact that this latent SMase activity is tightly coupled to the membrane bending properties suggests that it may be related to the general phenomenon of stress-induced ceramide synthesis and apoptosis. © 2012 Biophysical Society

Jaw biodynamic data for 24 patients with chronic unilateral temporomandibular disorder

This study assessed 24 adult patients, suffering from severe chronic unilateral pain diagnosed as temporomandibular joint (TMJ) disorder (TMD). The full dentate patients had normal occlusion and had never received an occlusal therapy, i.e., were with natural dental evolution/maturation. The following functional and dynamic factors were assessed: (1) chewing function; (2) TMJ remodeling or the condylar path (CP); and (3) lateral jaw motion or lateral guidance (LG). CPs were assessed using conventional axiography, and LG was assessed by K7 jaw tracking. Seventeen (71%) of the 24 (100%) patients consistently showed a habitual chewing side. The mean (standard deviation [SD]) of the CP angles was 47.90 (9.24) degrees. The mean (SD) of the LG angles was 42.95 (11.78) degrees. Data collection emerged from the conception of a new TMD paradigm where the affected side could be the habitual chewing side, the side with flatter lateral jaw motion or the side with an increased CP angle. These data may lead to improved diagnosis, therapy plans and evolution in TMD patients